I've had this table saw for over 10 years and it still works great.
One problem I haven't been able to figure out...the middle knob that
holds on the blade height wheel won't tighten the wheel so the blade
will stay put. It screws on completely but even if I tighten it with
a pair of pliers, the verticle height wheel still turns freely.

Any ideas on how to fix this? I've looked in the manual and I don't
see any washers or other parts missing.

Thanks for the help.